Telling people they are biased in their treatment of others – that they are racist or ageist, for example – can make them defensive and result in backlash. For this reason, change-makers nowadays often spread a different message: that stereotyping others isn’t a personal sin, but near-universal and something we must all aim to resist. However a new paper from researchers Michelle Duguid and Melissa Thomas-Hunt argues that this “Everyone Stereotypes” message, far from reducing bias, may actually encourage it.

In initial experiments, participants were simply asked to rate a particular group, such as women, on a series of stereotypical characteristics, which for women were: warm, family-oriented and (less) career-focused. Beforehand, half of the participants were told that “the vast majority of people have stereotypical preconceptions.” Compared to those given no messages, these participants produced more stereotypical ratings, whether about women, older people or the obese.

Another experiment used a richer measure of stereotyping – the amount of clichés used by participants in their written account of an older person’s typical day. This time, those participants warned before writing that “Everyone Stereotypes” were more biased in their writings than those given no message; in contrast, those told that stereotyping was very rare were the least clichéd of all. Another experiment even showed that hearing the “Everyone Stereotypes” message led men to negotiate more aggressively with women, resulting in poorer outcomes for the women.

The reason the “Everyone Stereotypes” message goes wrong can be found in a cornerstone of social psychology: we are more inclined to do something if others in our group are doing it. This means unspoken biases firm up when we believe them to be ubiquitous, and we may even react to counter-examples with greater hostility: as a man, a strong woman leader isn’t just a challenge to my assumptions, but questions the judgment of my entire gender.

Duguid and Thomas-Hunt also suspect their finding may generalise to perverse effects for other types of influencing, such as the use of statistics to emphasise injustice. For instance, after hearing that very few women inhabit CEO roles, business leaders might be galvanised to change – or, they might conclude that since their peers haven’t chosen to tackle the glass ceiling, perhaps there are good reasons to go slow themselves.

If this is true, what can be done? Portraying stereotyping as rare (or fiddling statistics) is simply misleading, while not discussing it at all is defeatist. A further experiment suggests a possible solution. In line with the other studies, men given the “Everyone Stereotypes” message were less likely to hire a hypothetical female job candidate who was assertive in arguing for higher compensation. But other men told that everyone tries to overcome their stereotypes were fairer than those who received no information at all. The participants were adjusting their behaviour to fit the group norms, but this time in a virtuous direction.

This approach essentially adopts the method found in many personal and organisational change philosophies, such as Appreciative Inquiry, of framing messages around a desired outcome rather than an unwanted situation. By uniting around what is good in us, we’re more likely to get welcome results.